The world’s most sensitive dark matter detector – the LUX-ZEPLIN (LZ) – is heading towards reality with the US Department of Energy giving a formal approval for the scope, cost and schedule for the whole project.
Dark matter has been elusive till date despite the fact that it makes up more than 85 per cent of the known Universe. Physicists have been working tirelessly to hunt the weakly interacting massive particles (WIMPs) which are theoretically the elementary particles of dark matter; however, there has been no luck yet. To put this unlucky streak to an end, scientists have been working to design a dark matter detector that will be far more sensitive than any dark matter detector ever built.
LZ receives its name from the Large Underground Xenon experiment (LUX) and the UK-based ZonEd Proportional scintillation in Liquid Noble gases experiment (ZEPLIN). LUX, a smaller liquid xenon-based underground experiment at SURF will be dismantled to make way for the new project.
Approval by US DoE means that the path is clear for building of the major components of the detector as well as for the preparation for the detector’s nearly mile-deep lair at the Sanford Underground Research Facility (SURF) in San Diego.
The experiment is designed to tease out dark matter signals from within a chamber filled with 10 metric tonnes of purified liquid xenon, one of the rarest elements on Earth.
“Nobody looking for dark matter interactions with matter has so far convincingly seen anything, anywhere, which makes LZ more important than ever,” said Murdock Gilchriese, LZ project director and physicist at the Lawrence Berkeley National Laboratory (Berkeley Lab).
Scientists, physicists and astronomers are thrilled with the capabilities of the dark matter detector and believe that the LZ project will lead science in testing one of the most attractive hypotheses for the nature of the dark matter.
“Liquid xenon has turned out to be a nearly magical substance for WIMP detection, as demonstrated by the sensitivities achieved by ZEPLIN and LUX,” said Henrique Araujo from Imperial College London, who leads the project in the UK.
The SURF site shields the experiment from many particle types that are constantly showering down on the Earth’s surface and would obscure the signals LZ is seeking. Some previous and planned experiments that also use liquid xenon as the medium for dark-matter detection are helping to set the stage for LZ.